[Ext] OpenDownload² 4.1.2

[Tuxman]

I run Firefox 57 at home now and there is literally no place to put a Run button anywhere; plus, AFAICS, the possibility to actually run an external application was removed. Sorry. Use Pale Moon or SeaMonkey if it is essential for you.

[Olofern]

I use Waterfox and OpenDownload² 4.1.2.
Please, can you add an option to avoid that the files inside the custom download folder will be purged?

[Tuxman]

Done for 4.2.0. I'm updating the website and I hope the Mozilla guys still let updates through.